Windscreen wiper device

ABSTRACT

A windscreen wiper device comprising an elastic, elongated carrier element, as well as an elongated wiper blade, which can be placed in abutment with a windscreen to be wiped, which wiper blade includes at least one longitudinal groove, in which groove a longitudinal strip of the carrier element is disposed, wherein ends of the longitudinal strip are connected to a respective connecting piece, which windscreen wiper device comprises a connecting device for an oscillating arm, wherein the wiper blade comprises an elongated upper holding part and an elongated lower wiping part of a flexible material, wherein the holding part comprises downwardly extending side arms for holding the wiping part from the outside in a lateral region thereof, wherein the holding part is provided with an elongated reinforcement element, and wherein the holding part and the reinforcement element are mutually connected through co-extrusion.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a windscreen wiper device comprising anelastic, elongated carrier element, as well as an elongated wiper blade,which can be placed in abutment with a windscreen to be wiped, whichwiper blade includes at least one longitudinal groove, in which groove alongitudinal strip of the carrier element is disposed, wherein ends ofthe longitudinal strip are connected to a respective connecting piece,which windscreen wiper device comprises a connecting device for anoscillating arm.

2. Related Art

Such a windscreen wiper device is known from international (PCT-) patentpublication no. WO 02/090155 in the name of the same Applicant. Theprior art windscreen wiper device is in particular designed as a“yokeless” wiper device or “flat blade”, wherein use is no longer madeof several yokes pivotally connected to each other, but wherein thewiper blade is biassed by the carrier element, as a result of which itexhibits a specific curvature. In this known windscreen wiper device thewiper blade includes two opposing longitudinal grooves on itslongitudinal sides, in which grooves spaced-apart longitudinal strips ofthe carrier element are disposed. Neighbouring ends of the longitudinalstrips are interconnected by the respective connecting piece.

A sometimes felt disadvantage of the windscreen wiper device asdescribed in the above international (PCT-) patent publication is that arubber wiping lip of the wiper blade might show a permanent deformationafter several months of use, as the wiping lip has to make manyoscillating movements during use, wherein the wiping lip has to bendseverely. Bending the rubber of the wiping lip many times back and forthmight lead to a permanent deformation of the rubber and thus todeteriorated wiping properties, with all negative consequences involved.

SUMMARY OF THE INVENTION

It is an object of the invention to improve the prior art, that is toimprove a windscreen wiper device known from the above international(PCT-) patent publication, wherein a permanent deformation of the wipinglip is avoided at all times.

In order to accomplish that objective, a windscreen wiper device of thekind referred to in the introduction according to the invention ischaracterized in that the wiper blade comprises an elongated upperholding part and an elongated lower wiping part of a flexible material,wherein the holding part holds the wiping part, wherein the holding partcomprises downwardly extending side arms, seen in cross-section, forholding the wiping part, from the outside in a lateral region thereof,wherein the holding part is provided with an elongated reinforcementelement, and wherein the holding part and the reinforcement element aremutually connected through co-extrusion. Preferably, the side arms ofthe holding part pivotally engage the wiping part from the outside in alateral region thereof, so that a mechanical articulation is realizedbetween the holding part and the wiping part, wherein the holding partholds the wiping part allowing the wiping part to make pivotal orhingeable movements relative to the holding part during use. In use thepivotal movements of the wiping part correspond to oscillatory movementsof the oscillating arm.

Due to the mechanical articulation the wiping part will not have to bendto follow the oscillatory movements of the oscillating arm, so that apermanent deformation of the wiping part as a result of stress in therubber thereof is avoided. The reinforcement element ensures that theholding part has a flexural or bending stiffness in transversedirection, so that the holding part is allowed to firmly hold the wipingpart.

In a preferred embodiment of a windscreen wiper device in accordancewith the invention, the reinforcement element extending in longitudinaldirection has a bending stiffness in transverse direction and isflexible in longitudinal direction. Particularly, the reinforcementelement is provided with spaced-apart profiles extending in transverseand longitudinal directions. Hence, the reinforcement element enhancesthe stiffness of the holding part in transverse direction, allowing theholding part to firmly retain the wiping part thereon. Simultaneously,the reinforcement element is flexible enough to follow any bending ofthe longitudinal strip along the curvature of the windscreen to bewiped. Accordingly, the reinforcement element incorporates two featureswhich at first sight appear to be incompatible, namely having a bendingstiffness in transverse direction and having flexibility in longitudinaldirection. This is particularly achieved by the profiles put at adistance form each other.

In another preferred embodiment of a windscreen wiper device accordingto the invention, the spaced-apart profiles have a C-shapedcross-section. In the alternative, first and second spaced-apartprofiles each having a C-shaped cross-section are provided, wherein theC s of the first and second profiles are different in size.

In another preferred embodiment of a windscreen wiper device inaccordance with the invention, the at least one longitudinal groovehaving a open circumference is provided on the holding part at an upperside thereof facing away from the wiping part. Particularly, thelongitudinal strip can be easily mounted inside the central groove byhand, for example. More in particular, longitudinal sides of the holdingpart are bend inwardly at the location of its upper side, therebydefining the longitudinal groove. Accordingly, the longitudinal strip isfirmly retained inside the groove. In the alternative, the holding parthas a central groove having a closed circumference.

In another preferred embodiment of a windscreen wiper device accordingto the invention, the side arms of the holding part pivotally engage thewiping part from the outside in a lateral region thereof. Particularly,the holding part further comprises additional downwardly extendingengaging means for pivotally engaging the wiping part in an upper regionthereof. The additional engaging means ensure that a wiping lip of thewiping part is tumbled over at each turning point of its oscillarymovement with the biggest reversal torque.

In another preferred embodiment of a windscreen wiper device inaccordance with the invention, the wiping part comprises a wiping lip, aneck extending from the wiping lip, as well as an enlarged headextending from the neck, and wherein the enlarged head is mounted into ahollow chamber defined by the side arms of the holding part. Theenlarged head preferably has a circular, elliptical, square,rectangular, rhomboid or heart-shaped cross-section. The wiping lip isplaced in abutment with a windscreen to be wiped. The wiping lip, theneck and the enlarged head particularly are in one piece and extend inlongitudinal direction along the entire length of the wiper blade.

Particularly, the additional engaging means engage the enlarged head atthe location of its upper surface. More in particular, the engagingmeans comprise a downwardly extending (elongated) protrusion engagingthe enlarged head in a correspondingly shaped slit thereof. Preferably,the protrusion extends along the entire length of the wiper blade and ismade in one piece with the holding part.

In another preferred embodiment of a windscreen wiper device accordingto the invention the arms of the holding part comprise inwardlyextending end parts, wherein the neck is located at least partly betweenthe end parts, and wherein the enlarged head is located above the endparts. In other words, the enlarged head is confined in the hollowchamber, wherein the hook-shaped end parts further retain the wipingpart onto the holding part. Particularly, the hollow chamber comprises alubricant in order to allow smooth pivotal movements of the wiping partwithout wear.

In another preferred embodiment of a windscreen wiper device accordingto the invention, the holding part is provided with a spoiler at a sidethereof facing away from the wiping part. The spoiler may be providedwith engaging members engaging around longitudinal sides of the holdingpart. Preferably, the spoiler is entirely detachably connected to theholding part. In the alternative, the spoiler is in one piece with theholding part.

The holding part and the wiping part preferably extend in longitudinaldirection along the entire length of the wiper blade. In other words,the wiper blade consists of two mutually cooperating constructionalelements, namely the holding part and the wiping part. The parts arepreferably slidably connected to each other, wherein the enlarged headof the wiping part is slidably mounted into the hollow chamber of theholding part. The hollow chamber extends along the entire length of thewiper blade so as to form a channel with two open ends. One of the openends of the channel forms an entrance through which the wiping part as aseparate construction element can be slid by hand into the channel untilthe wiping part is finally retained onto the holding part (the firstposition). The open end also acts as an exit through which the wipingpart can be slid by hand from the first position until the wiping partas a separate “loose” construction element can be replaced or repaired(the second position).

The wiping part is at least substantially made of an elastomericmaterial, such as rubber, wherein the holding part is at leastsubstantially made of a plastic material. The reinforcement element isparticularly made of metal.

THE DRAWINGS

The invention will now be explained in more detail with reference tofigures illustrated in a drawing, wherein:

FIG. 1 shows a perspective view of a windscreen wiper device accordingto a preferred embodiment of the invention; and

FIGS. 2, 3 and 4 are perspective views of parts of the windscreen wiperof FIG. 1, partly in exploded view.

DETAILED DESCRIPTION

FIG. 1 shows a preferred variant of a windscreen wiper device 1according to the invention, the windscreen wiper device 1 is built up ofa wiper blade 2 having a plastic elongated upper holding part 3 and anelastomeric elongated lower wiping part 4, both extending inlongitudinal direction along the entire length of the wiper blade 2. Inthe holding part 3 a central longitudinal groove 5 is formed, in which alongitudinal strip 6 made of spring band steel is fitted (FIGS. 2 and3). The strip 6 forms a flexible carrier element for the rubber wiperblade 2, as it were, which is thus biased in a curved position (thecurvature in operative position being that of a windscreen to be wiped).Outer ends of the strip 6 are connected on either side of the windscreenwiper device 1 to connecting pieces 7 functioning as clamping members.In this embodiment, the connecting pieces 7 are separate constructionalelements, which may be form-locked as well as force-locked to the outerends of the strip 6. In another preferred variant, the connecting pieces7 are in one piece with the strip 6 made of spring band steel.

The windscreen wiper device 1 is furthermore built up of a connectingdevice 8 of plastic or metallic material for an oscillating wiper arm 9.The connecting device 8 comprises clamping members 10 that are integraltherewith, which engage round longitudinal sides 11 of the holding part3 that face away from each other, as a result of which the connectingdevice 8 is firmly attached to the unit made up of the holding part 3and the strip 6. Likewise, the connecting pieces 7 comprise similarclamping members. The oscillating wiper arm 9 is pivotally connected tothe connecting device 8 about a pivot axis near one end thereof.

As can be seen from FIGS. 2 and 3, the holding part 3 is provided withdownwardly extending side arms 12 in one piece therewith, seen incross-section, thus defining a hollow chamber or space 13, again seen incross-section. The hollow chamber 13 extends in longitudinal directionalong the entire length of the wiper blade 2, so as to form a channelwith two open outer ends. Again referring to FIGS. 2 and 3, the wipingpart 4 comprises a wiping lip 14, a neck 15 extending from the wipinglip 14, as well as an enlarged head 16 extending from the neck 15 andhaving a heart-shaped cross-section. The parts 3,4 are slidablyconnected to each other, wherein the enlarged head 16 of the wiping part4 is slidably mounted into the hollow channel of the holding part 3. Oneof the open ends of the channel forms an entrance through which thewiping part 4 as a separate construction element can be slid by handinto the channel until the wiping part 4 is finally retained onto theholding part 3 (the first or holding position). The open end also actsas an exit through which the wiping part 4 can be slid by hand from thefirst position until the wiping part 4 as a separate “loose”construction element can be replaced or repaired (the second position).The side arms 12 of the holding part 3 pivotally engage the enlargedhead 16 of the wiping part 4, so as to allow a pivotal or hingeablemovement of the wiping part 4 when the oscillating wiper arm 9 attachedto the holding part 3 makes a corresponding oscillatory movement.

As shown, the holding part 3 is connected to a detachable spoiler 17 ata side thereof facing away from the wiping part 4, wherein the spoiler17 is equipped with engaging members engaging around longitudinal sides11 of the holding part 3. The longitudinal sides 11 are bend inwardly tofirmly retain the longitudinal strip 6 inside the groove 5.

With reference to FIGS. 2 and 3, a bottom of the holding part 3 isprovided with additional engaging means in the form of a downwardlyextending protrusion 18 which extends in longitudinal direction along apart of the length of the wiper blade 2 or along the entire lengththereof. The protrusion 18 engages into a correspondingly shaped slit 19provided on an upper surface of the hollow chamber 13 by means of freeends of the side arms 12 and the protrusion 18. Hence, an unstabledesign is obtained, wherein the torque is maximal when the wiping lip 14tumbles over at each turning point of its oscillatory movement.

The holding part 3 is provided with an elongated reinforcement 20element in one piece of metal, wherein the holding part 3 and thereinforcement element 20 are mutually connected through co-extrusion.The reinforcement element 20 extending in longitudinal direction alongthe entire length of the holding part 3 has a bending stiffness intransverse direction and is flexible in longitudinal direction. This isrealized by providing the reinforcement element 20 with profiles 21spaced-apart longitudinally from one another therealong by interveningportions, wherein the intervening portions, also referred to as bridges,differ in shape from the profiles 21, wherein the profiles are shown,for example, having a C-shaped or U-shaped cross-section (FIG. 2) andextending in transverse and longitudinal directions. In other words, byremoving (cutting, sawing, stamping, for example) material at regulardistances from the C-shape, a reinforcement element 20 is obtained withprofiles 21 having a C-shaped or U-shaped cross-section and beingpositioned at a constant distances from each other. With reference toFIG. 3, first and second spaced-apart profiles 21,22 are eachspaced-apart longitudinally from one another therealong by interveningportions, wherein the intervening portions, also referred to as bridges,differ in shape from the profiles 21,22 wherein the profiles are shown,for example, as each having a C-shaped cross-section, wherein the C ofthe first profiles 21 is smaller than the C of the second profiles 22.In both embodiments the reinforcement element 20 enhances the stiffnessof the holding part 3 in transverse direction, allowing the holding part3 to firmly retain the wiping part 4 thereon. Simultaneously, thereinforcement element 20 is flexible enough to follow any bending of thelongitudinal strip 6 along the curvature of the windscreen to be wiped.Accordingly, the reinforcement element 20 incorporates two featureswhich at first sight appear to be incompatible, namely having a bendingstiffness in transverse direction and having flexibility in longitudinaldirection. This is particularly achieved by the profiles 21,22 put at adistance from each other.

FIG. 4 corresponds to FIGS. 2 and 3, albeit that another embodiment ofthe reinforcement element 20 is shown. Further, longitudinal sides 11 ofthe holding part 3 are co-extruded relative to the central part 23 ofthe holding part 3, wherein the longitudinal sides 11 are made of astiffer material compared to the material of the central part 23.

Although not depicted in the figures, it will be clear for a personskilled in the art that the oscillating wiper arm 9 is connected to amounting head fixed for rotation to a shaft driven by a small motor. Inuse, the shaft rotates alternately in a clockwise and in acounter-clockwise sense carrying the mounting head into rotation also,which in turn draws the oscillating wiper arm 9 into rotation and bymeans of the connecting device 8 moves the wiper blade 2.

The invention is not restricted to the embodiments shown, but alsoextends to other preferred variants falling within the scope of theappended claims. For example, a skilled person would easily understandthat the central longitudinal strip 6 of FIGS. 2 and 3 could well bereplaced by two longitudinal strips 6 located in correspondingly shapedgrooves 5 in the holding part 3.

The invention claimed is:
 1. A yokeless windscreen wiper devicecomprising an elastic, elongated carrier element, as well as anelongated wiper blade, which can be placed in abutment with a windscreento be wiped, which wiper blade includes at least one longitudinal groovehaving an open circumference, in which groove a longitudinal strip ofthe carrier element is disposed, wherein ends of said longitudinal stripare connected to a respective connecting piece, which windscreen wiperdevice comprises a connecting device for an oscillating arm, said wiperblade comprises an elongated upper holding part and an elongated lowerwiping part of a flexible material, wherein said holding part comprisesdownwardly extending side arms for holding said wiping part from theoutside in a lateral region thereof, wherein said at least onelongitudinal groove having an open circumference is provided on saidholding part at an upper side thereof facing away from said wiping part,wherein said holding part is provided with an elongated reinforcementelement having profiles spaced-apart longitudinally from one anothertherealong by intervening portions, said intervening portions differingin shape from said profiles to provide said reinforcement element withan enhanced bending flexibility in the longitudinal direction and anenhanced bending stiffness in the transverse direction, and wherein saidholding part and said reinforcement element are mutually connectedthrough co-extrusion.
 2. A yokeless windscreen wiper device according toclaim 1, wherein said spaced-apart profiles have a C-shapedcross-section.
 3. A yokeless windscreen wiper device according to claim1, wherein said spaced-apart profiles include first and secondspaced-apart profiles having a C-shaped cross-section, and wherein saidC-shaped cross-sections of said first and second spaced-apart profilesare different in size.
 4. A yokeless windscreen wiper device accordingto claim 1, wherein said side arms of said holding part pivotally engagesaid wiping part from the outside in a lateral region thereof to allowsaid wiping part to pivot within said side arms of said holding part. 5.A yokeless windscreen wiper device according to claim 4, wherein saidholding part further comprises additional downwardly extending engagingmeans for pivotally engaging said wiping part in an upper regionthereof.
 6. A yokeless windscreen wiper device according to claim 5,wherein said additional downwardly extending engaging means engage anenlarged head of said wiping part.
 7. A yokeless windscreen wiper deviceaccording to claim 6, wherein said additional downwardly extendingengaging means comprise a downwardly extending protrusion engaging saidenlarged head in a slit thereof.
 8. A yokeless windscreen wiper deviceaccording to claim 1, wherein said wiping part comprises a wiping lip, aneck extending from said wiping lip, as well as an enlarged headextending from said neck, and wherein said enlarged head is mounted intoa hollow chamber defined by said side arms of said holding part, saidside arms engaging said enlarged head with said enlarged head being freeto pivot within said hollow chamber.
 9. A yokeless windscreen wiperdevice according to claim 8, wherein said enlarged head has one of acircular, elliptical, square, rectangular, rhomboid or heart-shapedcross-section.
 10. A yokeless windscreen wiper device according to claim8, wherein said side arms of said holding part comprise inwardlyextending end parts, and wherein said neck is located at least partlybetween said end parts and the enlarged head is located above said endparts.
 11. A yokeless windscreen wiper device according to claim 8,wherein said hollow chamber includes a lubricant.
 12. A yokelesswindscreen wiper device according to claim 1, wherein said holding partis provided with a spoiler at a side thereof facing away from saidwiping part.
 13. A yokeless windscreen wiper device according to claim12, wherein said spoiler is detachably connected to said holding part.14. A yokeless windscreen wiper device according to claim 12, whereinsaid spoiler is provided in one piece therewith engaging membersengaging around longitudinal sides of said holding part.